class_docstr: A stream operator for aggregating an entire history of a stream.
  
  Parameters
  ----------
  func : `Callable[[List[float]], float]`
      A function that aggregates the history of a stream.
code: def __init__(self, func: "Callable[[List[float]], float]") -> None:
      super().__init__()
      self.func = func
  
imports: from typing import Callable, List
  import numpy
  from tensortrade.feed.core.base import Stream
  from tensortrade.feed.api.float import Float
label_desc: Use image node_id 1 to create a new ExpandingNode object from inherited base classes: Stream with example: obj = ExpandingNode(func)